Understanding Structure and Response in Thermally-Responsive Block Copolymer Assemblies

了解热响应嵌段共聚物组件的结构和响应

• 批准号: 1105622
• 负责人: Robert Grubbs
• 金额: $ 34.5万
• 依托单位: SUNY at Stony Brook
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-07-01 至 2014-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1105622&HistoricalAwards=false
• 关键词: Understanding; Structure; Response; Thermally; Responsive

TECHNICAL SUMMARY:Responsive polymer assemblies show great promise in a range of applications, including drug delivery, sensing, and catalysis. Crucial to the elaboration of these systems is the development of polymers that undergo rapid, predictable, and reversible changes between assemblies with different sizes and structures. For applications involving encapsulation of other species within polymer vesicles, the development of more efficient encapsulation methods is also of great importance. To meet these challenges, the PI and co-workers have previously prepared temperature-responsive ABC triblock copolymers with poly(ethylene oxide) (PEO) as a hydrophilic block, poly(N-isopropylacrylamide) as a thermoresponsive block, and polyisprene as a cross-linkable hydrophobic block, which form assemblies that undergo large changes in size and shape around a critical temperature, however the reorganization of small assemblies (micelles of 20 nm diameter) into larger assemblies (vesicles of 100 nm diameter) at elevated temperatures was found to take several weeks. Recently, related copolymers with poly(butylene oxide-stat-ethylene oxide) responsive blocks, in which there are weaker interchain interactions in the absence of water, were found to undergo significant structural transformations within several hours. This research will probe the hypothesis that weakening interchain interactions in the dehydrated state is critical to increasing assembly transformation rate. This research will further the understanding of these block copolymer systems and their potential applications. Specifically, the PI and co-workers will investigate new hydrophilic-responsive-hydrophobic triblock copolymers, further probe possible structural transformations (e.g., micelle-to-worm-like micelle), more deeply investigate the kinetics of the assembly transformation process, and carry out encapsulation and release studies with block copolymer assemblies. The further study of these novel responsive systems offers the potential to expand and transform the applications of polymer-based nanostructures.NON-TECHNICAL SUMMARY:Nanometer-sized assemblies of polymer molecules show much promise in a range of applications, from the treatment of cancer and other diseases to the development of new sensory devices. This research will further our understanding of polymer assemblies that are designed to undergo specific changes in size and shape upon exposure to heat or other stimuli. In doing so, it will lay the groundwork for future efforts to use these materials in applications where the response to stimulus can be coupled to a specific application, such as release of a chemotherapy agent or the detection of specific molecules. This research will be carried out by graduate and undergraduate students as part of their scientific training and will involve collaboration with other researchers at Stony Brook University, Brookhaven National Laboratory, and Warwick University (UK). The PI will work through the State University of New York Louis Stokes Alliance for Minority Participation (SUNY LSAMP) program to recruit undergraduate students to participate in research in the chemistry department. Results of this work will be presented at internationally-attended scientific meetings and the PhD students involved in the project will maintain a website/blog through which they will be able to communicate their reflections on the project and the life of a scientific researcher to the general public.

技术摘要：响应性聚合物组件在药物输送、传感和催化等一系列应用中显示出巨大的前景。开发这些系统的关键是开发能够在不同尺寸和结构的组件之间经历快速、可预测和可逆变化的聚合物。对于涉及将其他物质封装在聚合物囊泡中的应用，开发更有效的封装方法也非常重要。为了应对这些挑战，PI和同事之前制备了温度响应性ABC三嵌段共聚物，其中聚环氧乙烷（PEO）作为亲水性嵌段，聚（N-异丙基丙烯酰胺）作为热响应性嵌段，聚异戊二烯作为交叉聚合物-可连接的疏水性嵌段，形成在临界温度附近尺寸和形状发生巨大变化的组件，但是将小组件（直径20 nm的胶束）重组为更大的组件（直径为 100 nm 的囊泡）在高温下需要几周的时间。最近，发现具有聚（环氧丁烷-静态环氧乙烷）响应性嵌段的相关共聚物在没有水的情况下链间相互作用较弱，在几个小时内经历了显着的结构转变。这项研究将探讨这样一个假设：在脱水状态下削弱链间相互作用对于提高组装转化率至关重要。这项研究将进一步了解这些嵌段共聚物系统及其潜在应用。具体来说，PI和同事将研究新型亲水响应疏水三嵌段共聚物，进一步探讨可能的结构转变（例如，胶束到蠕虫状胶束），更深入地研究组装转变过程的动力学，并进行嵌段共聚物组件的封装和释放研究。对这些新型响应系统的进一步研究为扩展和转变基于聚合物的纳米结构的应用提供了潜力。非技术摘要：聚合物分子的纳米尺寸组装体在一系列应用中显示出很大的前景，从癌症的治疗到其他疾病也有助于开发新的感觉装置。这项研究将进一步加深我们对聚合物组件的理解，这些聚合物组件在暴露于热或其他刺激时会发生尺寸和形状的特定变化。这样做将为未来将这些材料用于对刺激的响应可以与特定应用相结合的应用中奠定基础，例如化疗药物的释放或特定分子的检测。这项研究将由研究生和本科生作为其科学训练的一部分进行，并将与石溪大学、布鲁克海文国家实验室和华威大学（英国）的其他研究人员合作。 PI 将通过纽约州立大学路易斯斯托克斯少数族裔参与联盟 (SUNY LSAMP) 计划招募本科生参与化学系的研究。这项工作的结果将在国际参加的科学会议上展示，参与该项目的博士生将维护一个网站/博客，通过该网站/博客，他们将能够向公众传达他们对该项目和科学研究人员生活的看法民众。

项目成果

Synthesis and characterization of poly(ethylene oxide)/polylactide/polylysine tri-arm star copolymers for gene delivery

用于基因传递的聚环氧乙烷/聚丙交酯/聚赖氨酸三臂星形共聚物的合成和表征

• DOI: 10.1002/pola.28938
• 发表时间: 2018
• 期刊: Journal of Polymer Science Part A: Polymer Chemistry
• 作者: Wu, Tianyuan;Cai, Yu;Zhao, Xia;Ngai, Chai K.;Chu, Benjamin;Hsiao, Benjamin;Hadjiargyrou, Michael;Grubbs, Robert B.
• 通讯作者: Grubbs, Robert B.